The intent of the ongoing and proposed clinical project is to study the feasibility and efficacy of immunotherapy with BCG and allogeneic leukemic cells given supplementary to chemotherapy in the treatment of human leukemia. Parameters of non-specific immune competence and specific humoral immunity will be intensely monitored during the treatment. Special emphasis will be placed upon the development of humoral anti-blast antibody during immunotherapy of both acute and chronic myelogenous leukemia, the specificity of such antibody and its interaction in vitro with cell-mediated immune assay systems. These studies will provide a basis for determining the prognostic significance of immunological reactions to tumor antigens, and for refining current immunotherapeutic and immunodiagnostic techniques. BIBLIOGRAPHIC REFERENCES: Baker, M.A., Taub, R.N., Brown, S.M. and Ramachandar, K. Delayed cutaneous hypersensitivity in leukemia patients to autologous blast cells. Brit. J. Hematology, 27:627, 1975. Baker, M.A. and Taub, R.N. Platelet-induced tolerance in the production of heteroantisera to human leukemia-associated antigens. Immunological Methods, 1975 (in press).